In August, after a tense run-up to the default deadline, US lawmakers passed the Budget Control Act. The legislation that increased the debt ceiling contains $917 billion in cuts through 2021, which will probably affect core research agencies such as the National Institutes of Health, the National Science Foundation and the science office of the Department of Defense. But individuals involved in global health programs are also bracing for a hit come September, when Congress scrutinizes how to appropriate next year's federal budget, given the nation's tightened purse strings.

Global health leaders say they expect cuts across the board for the next fiscal year in programs that tackle HIV transmission, tropical disease reduction and infant mortality.

US-led programs likely to be affected include the Global Health Initiative (GHI), the US Agency for International Development (USAID) and the President's Emergency Plan for AIDS Relief (PEPFAR).

Some experts fear that the cuts could dampen recent successes in malaria control and HIV prevention. They add that, in addition to impeding overseas health programs in developing nations, the budget reductions might also trickle down through the economic slowdown to decelerate research spending in pharma, biotech and academia.

“We're on the cusp of research innovation in global health,” says Kaitlin Christenson, director of the Global Health Technologies Coalition, an umbrella organization representing more than 30 nonprofits that aims to bring awareness of how technologies can be used in the developing world. Recent research has shown promising developments in HIV prevention, including potential vaccines, microbicides and once-daily pill regimens.

“Unless the funding continues, we won't be able to continue the momentum,” she adds.

Appropriations for global health won't be known until after the August recess, but clues suggest that cuts are on the way. In July, the US House of Representatives Sub-committee on State and Foreign Operations Appropriations, the first of many hurdles for global health funding, proposed a GHI budget of $7.1 billion for the 2012 fiscal year—$2.7 billion less than President Barack Obama's request and $1.8 billion below this year's levels.

The uncertainty surrounding funding does not look set to be resolved anytime soon. On 3 August, the subcommittee postponed breaking down how proposed funding would be distributed. The House failed to vote on the general appropriations bill, and the Senate has not developed a companion bill yet.

In the 2011 fiscal year, the US maintained funding at $8.86 billion, a slim $50 million below the previous year's levels. “It is very difficult to plan ahead when the budgets are so uncertain,” says Aaron Emmel, government affairs officer with PATH, an international global health nonprofit based in Seattle. “There are a lot of question marks [around] how the fiscal 2012 budget will ultimately end up.”

“At this point, almost anything is at risk,” Christenson says. “We need champions on the issues. When we're talking about global health funding, we're talking about lives.”